Photovoltaic device having a stretchable carrier

ABSTRACT

A stretchable photovoltaic device, a stretchable photovoltaic module and a carrier for facilitating formation of a stretchable photovoltaic device and/or module are provided. The stretchable photovoltaic device includes a stretchable part, at least one photovoltaic cell and a surface over which that at least one photovoltaic cell is disposed. The stretchable part has a given length that is operable to change in response to a force being applied to the device. The given length may, for example, elongate when the force causes the device to elongate. Alternative and/or additionally, the given length may compress when the force causes the device to compress.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of co-pending U.S. patent applicationSer. No. 12/381,588, filed Mar. 13, 2009, which is herein incorporatedby reference in its entirety.

BACKGROUND Field

The following relates generally to photovoltaic devices, and moreparticularly to stretchable photovoltaic devices and carriers thatfacilitate formation of the same.

Related Art

Renewable energy, unlike conventional energy, is generated by harnessingone or more potentially limitless supplies of naturally replenishednatural resources, including, for example, sunlight, wind, rain, tidesand geothermal heat. Because of being generated as such, a significantportion of the World's populace realizes that renewable energy is everincreasing in importance because, for example, renewable energy providesways to supplant or augment conventional energy and/or to provide energywhere conventional energy does not or cannot be distributed.

Given that most sources of renewable energy are environmentally clean,many consider renewable energy as a way of reducing detrimental effectsto the environment (e.g., pollution, and in turn, global climate change)caused by generating conventional energy from fossil fuels. And given anever decreasing supply of the fossil fuels and concerns over peak oil,many believe that, in the near future, the sources of renewable energyneed not only to increase in amount, but also proliferate in type (eacha “renewable-energy source”).

In addition, certain renewable-energy sources may, as a result ofinherent characteristics thereof, spur development of new applicationsand/or cause re-development of existing applications to take advantagesuch sources. For example, some of the renewable-energy sources may havean inherent characteristic of being able to provide power without beingtethered to a remote distribution center. This characteristic may spurdevelopment of mobile and/or wireless applications, for example.Moreover, renewable energy may allow for deployment of certain types ofapplications that, but for a given type of source, would not bepracticable. On the other hand, a need for a certain type of applicationmay spur development of a new renewable-energy source or re-developmentof one or more of the renewable-energy sources.

Major contributors to current, worldwide generation of renewable energyare renewable-energy sources that employ a photovoltaic (“PV”) effect.Pursuant to the PV effect, each of these renewable-energy sources (“PVsource”) generates energy, in the form of electricity, by harnessingelectromagnetic radiation, such as sunlight, garnered from respective anenvironment proximate to such PV source.

Many applications for the PV source currently exist. These applicationsare not limited to any particular area of the world and/or any givensector of economy. In remote regions of the world, for example, anoff-grid installation of the PV source provide the only available sourceof electricity. In highly populated and/or economically developedregions, the PV source may, for example, source electricity to anelectrical grid to supplement and/or reduce the amount of conventionalenergy distributed from the electrical grid. Assuming that a cost perunit of energy provided from the PV source is less than a cost per unitof energy provided from a source of conventional energy, any savings incosts resulting from the PV source sourcing electricity to theelectrical grid may be realized by utility companies and passed on totheir customers.

To facilitate the foregoing in the past, a legacy PV source employseither a legacy PV panel or a legacy array of such PV panels(“photovoltaic-panel array”). Each of the legacy PV module and legacyphotovoltaic-panel array typically includes a plurality of legacy PVcells (sometimes referred to as solar cells) that are electricallyinterconnected.

Each of these legacy PV cells is constructed either rigidly or to allowa limited amount of flexing or bending. Damage, and in turn,inoperability of any of the legacy PV cells occurs when such legacy PVcell is subjected to (i) a force beyond the limited amount of flexing orbending, and/or (ii) a force that would cause it to elongate and/orcompress. Like the construction of the legacy PV cells, each of thelegacy PV module and legacy photovoltaic-panel array are generallyrigidly constructed so as to prevent damage to and inoperability of thelegacy PV cells that would otherwise result from the aforementionedforces.

As can be readily discerned from the foregoing, the legacy PV source isnot suitable for applications that require non-planar and/or arbitraryform factors. Therefore, there is a need in the art for a PV sourcesuitable for applications that require non-planar and/or arbitrary formfactors.

SUMMARY

A stretchable photovoltaic device, a stretchable photovoltaic module anda carrier for forming a stretchable photovoltaic device are provided.The stretchable photovoltaic device includes a stretchable part, atleast one photovoltaic cell and a surface over which that at least onephotovoltaic cell is disposed. The stretchable part has a given lengththat is operable to change in response to a force being applied to thedevice.

The given length may, for example, elongate when the force causes thedevice to elongate. Alternative and/or additionally, the given lengthmay compress when the force causes the device to compress.

BRIEF DESCRIPTION OF THE DRAWINGS

So the manner in which the above recited features are attained and canbe understood in detail, a more detailed description is described belowwith reference to Figures illustrated in the appended drawings.

The Figures in the appended drawings, like the detailed description, areexamples. As such, the Figures and the detailed description are not tobe considered limiting, and other equally effective examples arepossible and likely. Furthermore, like reference numerals in the Figuresindicate like elements, and wherein:

FIGS. 1A and 1B are simplified plan view diagrams illustrating anexample carrier for facilitating formation of any of a stretchablephotovoltaic device and stretchable photovoltaic module;

FIGS. 2A and 2B are simplified plan view diagrams illustrating anexample stretchable photovoltaic device;

FIG. 3 is a simplified plan view diagram illustrating an examplestretchable photovoltaic device;

FIGS. 4A and 4B are simplified plan view diagrams illustrating anexample carrier for facilitating formation of any of a stretchablephotovoltaic device and stretchable photovoltaic module;

FIGS. 5A, 5B and 5C, are simplified plan view diagrams illustratingfirst, second and third form factors of a stretchable carrier;

FIGS. 6A and 6B are simplified plan view diagrams illustrating anexample stretchable photovoltaic device;

FIGS. 7A and 7B are simplified plan view diagrams illustrating anexample stretchable photovoltaic device;

FIG. 8 is a simplified plan view diagram illustrating an example carrierfor facilitating formation of any of a stretchable photovoltaic deviceand stretchable photovoltaic module;

FIG. 9 is a simplified plan view diagram illustrating an example carrierfor facilitating formation of any of a stretchable photovoltaic deviceand stretchable photovoltaic module;

FIGS. 10A-10B are simplified plan view diagrams illustrating an examplestretchable photovoltaic device;

FIGS. 11A-11B are simplified plan view diagrams illustrating an examplestretchable photovoltaic device;

FIGS. 12A-12B are simplified plan view diagrams illustrating an examplestretchable photovoltaic module;

FIG. 13 is a simplified plan view diagram illustrating an examplestretchable photovoltaic module;

to FIG. 14 is a simplified plan view diagram illustrating an examplestretchable photovoltaic device;

FIG. 15 is a simplified plan view diagram illustrating an examplestretchable photovoltaic device;

FIG. 16 is a simplified plan view diagram illustrating an examplestretchable photovoltaic device;

FIGS. 17A and 17B are simplified plan view diagrams illustrating anexample stretchable PV device 1700;

FIGS. 18A and 18B are simplified plan view diagrams illustrating anexample stretchable PV device;

FIG. 19 is a flow diagram illustrating an example process for forming astretchable photovoltaic device under monolithic formation;

FIG. 20 is a flow diagram illustrating an example process 1900 forforming a stretchable photovoltaic device under hybrid formation;

FIGS. 21 through 24 depict simplified plan view diagrams illustratingexample stretchable PV device 2100 having different types of stretchableparts according to some embodiments of the invention;

FIG. 25 depicts a stretchable carrier formed entirely of a wire meshaccording to some embodiments of the invention; and

FIG. 26 depicts a stretchable carrier and a plurality of PV cellsaccording to some embodiments of the invention.

DETAILED DESCRIPTION

In the following detailed description, numerous specific details are setforth in order to provide a thorough understanding of exemplaryembodiments or other examples described herein. However, it will beunderstood that these embodiments and examples may be practiced withoutthe specific details. In other instances, well-known methods,procedures, components and circuits have not been described in detail,so as not to obscure the following description. Further, the embodimentsdisclosed are for exemplary purposes only and other embodiments may beemployed in lieu of, or in combination with, the embodiments disclosed.

As used herein, the term “stretchable” describes a behavior of a givendimension (e.g., any of a length, width and height) of the stretchablephotovoltaic (“PV”) device, stretchable PV module, carrier forfacilitating formation of a stretchable PV device or module or one ormore elements thereof (each a “stretchable element”); this behaviorbeing that the given dimension changes in response to a force beingapplied to at least a portion of the stretchable element. For example,the term stretchable describes the behavior of the given dimension,responsive to the force subjecting the stretchable element to anelongation (“elongating force”), to elongate from an untensionedcondition. The term stretchable may also describe the behavior of thegiven dimension, responsive to the force subjecting the stretchableelement to a compression (“compressing force”), to compress from theuntensioned condition.

The term stretchable also describes the behavior of the given dimensionto return to (or, to a substantial degree to) the unchanged conditionor, alternately, to remain in its changed condition after releasing theforce being applied to at least a portion of the stretchable element.This may include, for example, the behavior of the given dimension toreturn to (or, to a substantial degree to) the untensioned conditionafter releasing any of the elongating or compressing forces applied tothe stretchable element. Alternatively, the term stretchable maydescribe the behavior of the given dimension to remain in an elongatedor in a compressed condition after releasing the elongating force or thecompressing force, respectively.

FIGS. 1A and 1B are simplified plan view diagrams illustrating anexample carrier 100 for facilitating formation of any of a stretchablePV device and stretchable PV module. The carrier 100 includes astretchable substrate 102. The stretchable substrate 102 defines anupper surface 104, a lower surface 106, a plurality of corrugations 108₁ . . . 108 _(n), and side edges 105, 107, 109 and 111

The upper surface 104 defines an upper-surface area, which is delimitedby the side edges 105-111. In addition, the upper surface 104 provides afoundation onto or over which one or more PV cells (not shown) may bedisposed. This foundation (“PV-supporting foundation”) may include theentire upper-surface area or, alternatively, one or more portions of theupper-surface area. In the latter case, the portions of the uppersurface area may be contiguous or, alternatively, dispersed.

The corrugations 108 ₁ . . . 108 _(n) may be, for example, periodic ornon-periodic undulations. The corrugations 108 ₁ . . . 108 _(n) havecorresponding amplitudes (“corrugation amplitudes”) 110 ₁ . . . 110 _(n)and widths (“corrugation widths”) 112 ₁ . . . 112 _(n). Each of thecorrugation amplitudes 110 ₁ . . . 110 _(n) may have the samedimensions, and in turn, each of the corrugation widths 112 ₁ . . . 112_(n) may have the same dimensions. Alternatively, one or more of thecorrugation amplitudes 110 ₁ . . . 110 _(n) may differ, and/or one ormore of the corrugation widths 112 ₁ . . . 112 _(n) may differ.

Together, the corrugation widths 112 ₁ . . . 112 _(n) define a length(“stretchable-part length”) 114 of the stretchable substrate 102. Thestretchable substrate 102 includes or is formed from one or morematerials, such as metal or plastic foils, which allow one or more ofthe corrugation widths 112 ₁ . . . 112 _(n), and in turn, thecorresponding corrugation amplitudes 110 ₁ . . . 110 _(n) to change(e.g., bend, elongate or compress) responsive to one or more forces(e.g., bending, elongating and/or compressing forces) applied to thecarrier 100 or stretchable substrate 102. Changes to the corrugationwidths 112 ₁ . . . 112 _(n), and in turn, resultant changes to thecorrugation amplitudes 110 ₁ . . . 110 _(n) result in thestretchable-part length 114 changing its previous state.

Although the foregoing describes the upper surface 104 as providing thePV-supporting foundation, the lower surface 106 may instead provide thePV-supporting foundation. Alternatively, the upper surface 104 mayprovide a first PV-supporting foundation for a first set of PV cells,and the lower surface 106 may provide a second PV-supporting foundationfor a second set of PV cells. This way, the carrier 100 may facilitateforming a PV device or module that has PV cells facing in more than onedirection.

FIGS. 2A and 2B are simplified plan view diagrams illustrating anexample stretchable PV device 200. The stretchable PV device 200includes the stretchable substrate 102 (FIG. 1) and a PV cell 202.

The stretchable PV device 200 also includes first and second outputterminals 205, 207. A load (not shown) may be coupled between the firstand second output terminals 205, 207 to permit a flow of a current. Inoperation, the current may flow (in terms of electron movement) to thefirst output terminal 205, thereby placing the first output terminal 205at a potential greater than that of the second output terminal 207.Therefore, for the sake of convention, the first output terminal 205 maybe referred to as a “positive” output terminal 205, and the secondoutput terminal 207 may be referred to as an “negative” output terminal207.

The PV cell 202 may include a PV stack 204 (FIG. 2A) along with firstand second conductors 209, 211. The PV stack 204 may include one or morelayers (“PV-stack layers”) made from thin-film materials. The PV-stacklayers may include, for example, front and back contact layers 210, 212that sandwich n-type and p-type semiconductor layers 206, 208, whichtogether form a single PV junction. The contact layers 210 and 212 maybe connected to either output terminal 205 or terminal 207. The PV-stacklayers may also include one or more optional buffer and other purposelayers (not shown) interleaved between the front and back contact layers210, 212 or, alternatively, positioned outside of the front and/or backcontact layers 210, 212. To increase efficiency over that afforded bythe single PV junction, the PV stack 204 may define multiple PVjunctions. To facilitate this, the PV-stack layers may includeadditional sets of n-type and p-type semiconductor layers.

The thin-film materials for forming the n-type and p-type semiconductorlayers 206, 208 may include any of amorphous silicon (“a-Si”),copper-indium-gallium diselenide (“CIGS”), cadmium telluride (“CdTe”),alloys of CdTe (“CdTe alloys”), alloys of silicon germanium (“SiGealloys”), conducting polymers and oligomers. The thin-film materials forforming the front and back contact layers 210, 212 and the buffer andother purpose layers generally depend upon the materials of the n-typeand p-type semiconductor layers 206, 208, and as such, may be materialsthat are compatible with the a-Si, GIGS, CdTe, CdTe alloys, SiGe alloys,quantum dots, organic dyes, conducting polymers and oligomers.

To increase efficiency over that afforded by the single PV junction, thePV stack 204 may define multiple PV junctions. For example, the PV stack204 may include a first junction having a GIGS layer with acharacteristic bandgap in a range of 1.75 eV, and a second junction havea GIGS layer with a characteristic bandgap in a range of 1.1 eV, therebyproviding a conversion efficiency in a range of 15-25%, The PV stack 204may define additional PV junctions as well.

To facilitate the additional PV junctions, the PV stack 204 may includean additional set of n-type and p-type semiconductor layers for each ofthe additional PV junction. The thin-film materials for forming each ofthese sets may differ from the thin-film materials of the n-type andp-type semiconductor layers 206, 208. For example, the thin-filmmaterials of the n-type and p-type semiconductor layers 206, 208 may becopper-gallium selenide (CuGaSe₂ or “CGS”) and the thin-film materialsof another set of n-type and p-type semiconductor layers may becopper-indium diselenide (CuInSe₂ or “CIS”). CGS is, at least partiallytransparent; so positioning the n-type and p-type semiconductor layers206, 208 closer than the other set of n-type and p-type semiconductorlayers 206, 208 to incident electromagnetic radiation takes advantage ofsuch transparency.

Although shown as being homogeneous and contiguous, each of the PV-stacklayers may include portions of one or more of the other layers(“other-layer portions”), and/or other elements of the stack 204(“miscellaneous-stack elements”), such as vias. The other-layer portionsand/or the miscellaneous-stack elements may be wholly contained withinone or a subset of the PV-stack layers. Alternatively, the other-layerportions and/or the miscellaneous-stack elements may extend through theentire or substantially all of the stack 204.

The first and second conductors 209, 211 may be coupled to additionaland optional front and back contact layers 210, 212, respectively. Tofacilitate this, the first and second conductors 209, 211 are made fromelectrically conductive materials that are compatible with the thin-filmmaterials of the front and back contact layers 210, 212. Furthermore,conductors 209 and 211 may be produced in the form of strip lines,busbars, grids, and the like. Additional layers for mechanical supportand/or electrical insulation may be included in the PV stack 204.

The first and second conductors 209, 211 permit the current to flow toand/or from the front and back contact layers 210, 212. The current mayflow to the front contact layer 210 or, alternately, to the back contactlayer 212 depending on the thin-film materials used for the n-type andp-type semiconductor layers 206, 208. For example, in an operatingGIGS-type cell, electrons flow from front contact 210 into contact layer212 so that conductor 209 may be coupled to the negative terminal andconductor 211 may be connected to the positive terminal.

If the thin-film materials used for the n-type and p-type semiconductorlayers 206, 208 dictate that the current flows to the front contactlayer 210, then (i) the first conductor 209 may couple the front contactlayer 210 to the first-output terminal 205; and (ii) the secondconductor 211 may couple the back contact layer 212 to the second-outputterminal 207. If, on the other hand, the thin-film materials used forthe n-type and p-type semiconductor layers 206, 208 dictate that thecurrent flows to the back contact layer 212, then the first conductor209 may interconnect the back contact layer 212 to the first-outputterminal 205; and the second conductor 211 may interconnect the frontcontact layer 212 to the second-output terminal 207. Depending onlocations of the first and second output terminals 205, 207, the firstconductor 209 and/or the second conductor 211 may include respectivevias to facilitate appropriate interconnection of the first and secondoutput terminals 205, 207.

The PV cell 202 may be disposed onto the upper surface 104 of thestretchable substrate 102 such that the entire or substantially all ofthe back-contact layer 212 affixes to the upper surface 104 and conformsto the undulating corrugations 108 ₁ . . . 108 _(n). Alternatively, thePV cell 202 may be disposed onto the upper surface 104 such that theback-contact layer 212 affixes to upper surface 104 only at certainlocations with or without conforming to the undulating corrugations 108₁ . . . 108 _(n). This way, the PV cell 202 and the stretchablesubstrate 102 may elongate and/or compress at different rates, and/orwithin different limits of elongation and/or compression.

Although not shown, the stretchable PV device 200 may include one ormore buffer layers between the PV cell 202 and the stretchable substrate102 to facilitate reduction of stresses and/or strains due to the PVcell 202 and the stretchable substrate 102 having different rates ofelongation and/or compression, and/or having different limits ofelongation and/or compression. And depending on desired orientation ofthe stack 204 and/or application, a layer of the stack 204 other thanthe back-contact layer 212 (e.g., a buffer layer of the stack 204) maybe disposed onto or over the upper surface 104 of the stretchablesubstrate 102. Additionally, the stretchable PV device 200 may include aplurality of PV cells, even though it is shown as including only one PVcell, namely, PV cell 202. Each of the plurality of PV cells may includeone or more PV junctions.

As described in more detail below, the stretchable PV device 200 may beformed monolithically (i.e., undergo “monolithic formation”) or hybridly(i.e., undergo “hybrid formation”). Under monolithic formation, thestretchable PV device 200 may be formed by (i) forming the stretchablesubstrate 102, (ii) depositing the PV cell 202 or plurality of PV cellsonto or over the upper surface 104 of the stretchable substrate 102, and(iii) then carrying out appropriate post-deposition processes (e.g.,using any of mechanical and laser scribing to monolithicallyinterconnect the plurality of PV cells).

Under hybrid formation, the stretchable PV device 200 may be formed byforming the stretchable substrate 102 and the PV cell 202 or pluralityof PV cells separately from one another using separate processes.Thereafter, the PV cell 202 or plurality of PV cells may be affixed ontoor over the upper surface 104 of the stretchable substrate 102 using abonding agent or adhesive. After the PV cell 202 or plurality of PVcells become affixed to the stretchable substrate 102, appropriatepost-affixing processes may be carried out. For example, the pluralityof PV cells may be interconnected using any of wire bonds, corrugatedtabs, tapes and like-type electrical interconnections. In generally, anyother type of PV cells can be employed, including those on rigidsubstrates, to produce stretchable PV devices. For example, crystallineor polycrystalline silicone cells may be assembled on a stretchablecarrier to produce a stretchable PV module. Other examples include GaAssingle-junction cells, III-V multi-junction cells, CdTe cells on glasssubstrates, and like type PV cells on glass substrates.

Analogous to the carrier 100 of FIG. 1, the stretchable PV device 200includes or is formed from one or more materials that allow one or moreof the corrugation widths 112 ₁ . . . 112 _(n), and in turn, thecorresponding corrugation amplitudes 110 ₁ . . . 110 _(n) to changeresponsive to one or more forces applied (“applied forces”) to thestretchable PV device 200 or elements thereof. In one particularconstruction of the stretchable PV device 200, for example, thestretchable substrate 102 may be a foil that is formed from metals ormetal alloys, including any of titanium, aluminum, copper, stainlesssteel, etc., and/or plastics, including any of polyimide, polyethylene,ethylene vinyl acetate (“EVA”), etc. The foil may have a thickness in arange of 10 to 200 microns or, alternatively, in a range of 25 to 100microns. In the untensioned condition, the undulating corrugations 108 ₁. . . 108 _(n) are in sinusoidal form; and the corrugation widths 112 ₁. . . 112 _(n) and corrugation amplitudes 110 ₁ . . . 110 _(n) may haveperiods and amplitudes in a range of 0.1 to 20 mm or, alternatively, ina range of 0.5 to 10 mm. One or more of these periods and amplitudes mayexhibit changes responsive to the applied forces.

In response to the applied forces causing one or more of the corrugationamplitudes 110 ₁ . . . 110 _(n) to flatten from the untensionedcondition, for example, may cause widening of the correspondingcorrugation widths 112 ₁ . . . 112 _(n). This widening results inincreases in the periods of the corresponding corrugation widths 112 ₁ .. . 112 _(n) from the untensioned condition. Alternatively and/oradditionally, the corresponding corrugation widths 112 ₁ . . . 112 _(n)may undergo narrowing in response to the applied forces causing one ormore of the corrugation amplitudes 110 ₁ . . . 110 _(n) to increases inamplitude from the untensioned condition. The narrowing results indecreases in the periods of the corresponding corrugation widths 112 ₁ .. . 112 _(n) from the untensioned condition.

The changes to the periods of the corrugation widths 112 ₁ . . . 112_(n), and in turn, resultant changes amplitudes to the corrugationamplitudes 110 ₁ . . . 110 _(n) (or vice versa) result in thestretchable-part length 114 exhibiting a change(“stretchable-part-length change”) from the untensioned condition or,alternatively, another previous state (e.g., a state other than theuntensioned condition). The stretchable-part-length change is indicativeof the stretchable-part length 114 in a condition (“changed condition”)that results from the stretchable substrate 102 being subjected to theapplied forces.

To facilitate determining the stretchable-part-length change, thestretchable-part length 114 may define first and second measures thatmay be measured in accordance with given units of measure of a referenceor standard for measuring physical dimensions (e.g., meters). Thesefirst and second measures may represent, for example, thestretchable-part length 114 in the untensioned condition or previousstate (“previous-length measure”) and the stretchable-part length 114 inthe changed condition (“changed-length measure”), respectively. Thestretchable-part-length change may be or be indicative of a differencebetween the previous-length and changed-length measures.

Given the corrugations 108 ₁ . . . 108 _(n), the stretchable-part-lengthchange, in general, is proportional to a ratio of the corrugationamplitudes 110 ₁ . . . 110 _(n) to the corrugation widths 112 ₁ . . .112 _(n). And relative to the untensioned condition or other previousstate, the stretchable-part-length change may be in excess ofone-hundred percent of the untensioned-length measure. This may occur,for example, when any one of the corrugation amplitudes 110 ₁ . . . 110_(n) is larger than its corresponding corrugation widths 112 ₁ . . . 112_(n). The changed-length measure may have a maximum that is less thancomplete extension or compression of the corrugation widths 112 ₁ . . .112 _(n) (i.e., less than maximum displacement or complete flattening ofthe corrugation amplitudes 110 ₁ . . . 110 _(n)) due to restrictionsimposed by properties of the PV stack 204. These restrictions mayinclude, for example, one or more maximum stress levels established toprevent micro-cracking and/or other failure mechanisms caused by overstressing the PV stack 204 or elements thereof.

Referring now to FIG. 3, a simplified plan view diagram illustrating across section of an example stretchable PV device 300 is shown. Thestretchable PV device 300 is similar to the stretchable PV device 200 ofFIG. 2, except as described below. The stretchable PV device 300includes an encapsulation 302. This encapsulation 302 that encapsulatesthe stretchable PV device 200. The encapsulation includes first andsecond coversheets 304, 306 separated by a thick layer of encapsulatingmaterial 308.

The encapsulating material 308 may be liquid, viscous, gelatinous orelastic so that the stretchable PV device 300 has a range of motion thatis substantially equivalent to or at least not appreciably limited overa range of motion of afforded by the stretchable PV device 200 withinthe encapsulation 302. One example of a suitable material for theencapsulation material 308 is silicone.

The coversheets 304, 306 may be elastic or elastic-like materials sothat the range of motion of the stretchable PV device 300 issubstantially equivalent to or at least not appreciably limited over therange of motion of the stretchable PV device 200 within theencapsulation 302. One example of a suitable material for any of thecoversheets 304, 306 is a sheet formed from latex.

Alternatively, any of the coversheets 304, 306 and encapsulatingmaterial 308 may include materials that can be made to entirely,substantially or otherwise limit the range of motion of the stretchablePV device 300. These materials may include, for example, heat-activatedand/or catalyst-inhibited passivation gelatins or sheets that remain ina flexible or semi-flexible state until being exposed to heat or achemical reaction, whereupon the encapsulation 302 hardens to any numberof degrees of hardness. Under this construction, the stretchable PVdevice 300 may be formed or worked into a desired shape or form factorwhen the encapsulation 302 is in the flexible or semi-flexible state,and after achieving the desired shape, the encapsulation 302 may undergohardening to achieve a given degree of hardness.

The given degree of hardness may limit the range of motion of thestretchable PV device 300 so as to allow for elastic or elastic-likebending or plastic or plastic-like deformation, but not elongation orstretching. Alternatively, the given degrees of hardness may make thestretchable PV device 300 rigid or otherwise un-stretchable.

As an alternative, the encapsulation 302 might not include theencapsulating material 308, and the coversheets 304, 306 may beinelastic materials, such as thermoplastic, composite plastics, acrylicglass and metal foils. Under this construction, the stretchable PVdevice 200 may be formed or worked into a desired shape or form factor.Thereafter, the coversheets 304, 306 may be applied to encapsulate, atleast in part, the stretchable PV device 200 to achieve the given degreeof hardness, and in turn, maintain the stretchable PV device 300 in thedesired shape or form factor.

Maintaining the stretchable PV device 300 in the desired shape or formfactor beneficially improves reliability and performance over a lifetimeof the PV device 300. A wider range of packaging materials, particularlyinflexible materials, may be used. In any case, the encapsulation 302may afford protection against degradation of the PV device 200 and theelements thereof, including for example, the first and second conductors209, 211 and exposed layers of the PV stack 204, caused by moisture,oxidation, and other chemical and/or mechanical detrimental effects.

As shown, the encapsulation 302 entirely encapsulates the stretchable PVdevice 200. The encapsulation 302, however, may only encapsulate aportion of the stretchable PV device 200.

FIGS. 4A and 4B are simplified plan view diagrams illustrating anexample stretchable carrier 400 for facilitating formation of any of astretchable PV device and stretchable PV module. The stretchable carrier400 includes a concatenation of five stretchable parts 404 ₁ . . . 404 ₅(collectively “stretchable parts 404”) and four mounting sites 402 ₁ . .. 402 ₄ (collectively “mounting sites 402”) arranged in an alternatingsequence starting with the first stretchable part 404 ₁ and ending withthe fifth stretchable part 404 ₅.

Each of the stretchable parts 404 ₁ . . . 404 ₅ may include or embodythe stretchable substrate 102 of FIG. 1, for example. The fivestretchable parts 404 ₁ . . . 404 ₅ include respective sets ofcorrugations (“corrugation sets”). The corrugations of each of thecorrugation sets may be, for example, periodic or non-periodicundulations, and have corresponding corrugation amplitudes andcorrugation widths. Each of the corrugation amplitudes may be the samedimensionally, and in turn, each of the corrugation widths may be thesame dimensionally. Alternatively, one or more of the corrugationamplitudes may differ, and/or one or more of the corrugation widths maydiffer.

The corrugation widths of the first corrugation set define a firststretchable-part length 406 ₁. The corrugation widths of the secondcorrugation set define a second stretchable-part length 406 ₂. Thecorrugation widths of the third corrugation set define a thirdstretchable-part length 406 ₃. The corrugation widths of the fourthcorrugation set define a fourth stretchable-part length 406 ₄. And thecorrugation widths of the fifth corrugation set define a fifthstretchable-part length 406 ₅.

The first stretchable part 404 ₁ includes or is formed from one or morematerials, such as metal or plastic foils, which allow one or more ofthe corrugation widths of the first corrugation set, and in turn, thecorresponding corrugation amplitudes of the first corrugation set tochange responsive to one or more of the applied forces applied to thestretchable carrier 400 or the stretchable part 404 ₁. The changes tothe corrugation widths of the first corrugation set, and in turn,resultant changes to the corrugation amplitudes of the first corrugationset result in the first stretchable-part length 406 ₁ changing from itsprevious state.

Each of the second, third, fourth and fifth stretchable parts 404 ₂ . .. 404 ₅ may be constructed differently from the first stretchable part404 ₂ or from materials that differ from the first stretchable part 404₁. This may be beneficial in that the differing constructions andmaterials may provide differing amounts of resistance. For simplicity ofexposition, however, the following assumes that each of the second,third, fourth and fifth stretchable parts 404 ₂ . . . 404 ₅ are the sameor substantially the same as the first stretchable part 404 ₁.

Each of the four mounting sites 402 ₁ . . . 402 ₄ may be flat or curved,rigid or flexible. The four mounting sites 402 ₁ . . . 402 ₄ includerespective upper surfaces 408 ₁ . . . 408 ₄ and respective lowersurfaces 410 ₁ . . . 410 ₄. Any of the four upper surfaces 408 ₁ . . .408 ₄ and four lower surfaces 410 ₁ . . . 410 ₄ may provide a foundationonto or over which one or more PV cells (not shown) may be disposed. Forsimplicity of exposition, the following assumes that each of the fourupper surfaces 408 ₁ . . . 408 ₄ provides the foundation onto or overwhich the PV cells may be disposed. And given that each of the fourupper surfaces 408 ₁ . . . 408 ₄ defines a given surface area, thefoundation may include either the entire surface area or portionsthereof. In the latter case, the portions of the surface area may becontiguous or, alternatively, dispersed.

Like the four mounting sites 402 ₁ . . . 402 ₄, the five stretchableparts 404 ₂ . . . 404 ₅ include respective upper surfaces 412 ₁ . . .412 ₅ and respective lower surfaces 414 ₁ . . . 414 ₅. Any of the fiveupper surfaces 412 ₁ . . . 412 ₅ and the five lower surfaces 414 ₁ . . .414 ₅ may provide a foundation onto or over which one or more PV cells(not shown) may be disposed. For simplicity of exposition, the followingassumes that each of the five upper surfaces 412 ₁ . . . 412 ₅ providesthe foundation onto or over which the PV cells may be disposed. Andgiven that each of the five upper surfaces 412 ₁ . . . 412 ₅ defines agiven surface area, the foundation may include either the entire surfacearea or portions thereof. In the latter case, the portions of thesurface area may be contiguous or, alternatively, dispersed.

Each of the five stretchable parts 404 ₂ . . . 404 ₅ may be, in whole orin part, electrically conductive, thermally conductive, electricallyinsulating and/or thermally insulating. Similarly, each of the fourmounting sites 402 ₁ . . . 402 ₄ may be, in whole or in part,electrically conductive, thermally conductive, electrically insulatingand/or thermally insulating. Each of the four mounting sites 402 ₁ . . .402 ₄ may include (or have formed thereon) one or moreelectrically-conductive contact (“mounting-site contacts”). Thesemounting-site contacts may be positioned to couple to and/or couple toone or more conductors of PV cells disposed over the four mounting sites402 ₁ . . . 402 ₄ (e.g., one or more of the first and second conductors209, 211 of the PV cell 202 of FIG. 2). If coupled to such conductors,then the mounting-site contacts may be isolated by one or moreelectrically-insulating portions.

The mounting-site contacts may interconnect to otherelectrically-conductive portions of the four mounting sites 402 ₁ . . .402 ₄ and/or electrically-conductive portions of the five stretchableparts 404 ₂ . . . 404 ₅ to form interconnection paths. Theseinterconnection paths, as described in more detail below, mayinterconnect the PV cells in series and/or parallel.

Although the stretchable carrier 400, as shown, includes fivestretchable parts 404 ₁ . . . 404 ₅ and four mounting sites 402 ₁ . . .402 ₄, the carrier stretchable 400 may include more of fewer stretchableparts and/or mounting sites. And although the concatenation of the fivestretchable parts 404 ₁ . . . 404 ₅ and four mounting sites 402 ₁ . . .402 ₄ is shown as a linear concatenation, the concatenation may takeother (e.g., geometric) forms as well.

Referring now to FIGS. 5A, 5B and 5C, simplified plan view diagramsillustrating first, second and third form factors 502, 504 and 506 ofthe stretchable carrier 400 of FIG. 4. The first form factor 502 definesan untensioned condition of the stretchable carrier 400. In theuntensioned condition, the stretchable carrier 400 or the elementsthereof are is not being subject to applied forces that cause any of thefive stretchable-part lengths 406 ₁ . . . 406 ₅ to change.

The second form factor 504 defines a curved form of the stretchablecarrier 400. In this condition, the stretchable carrier 400 and/or theelements thereof are being subject to one or more of the applied forcesin multiple directions that, in turn, cause one or more of the fivestretchable-part lengths 406 ₁ . . . 406 ₅ to elongate from theuntensioned condition so as to cause the stretchable carrier 400 toexhibit an arc or semi-circular form.

The third form factor 506 defines a linear stretched condition of thestretchable carrier 400. In this linear stretched condition, thestretchable carrier 400 and/or the elements thereof are being subject toone or more of the applied forces in a direction X that, in turn, causeone or more of the five stretchable-part lengths 406 ₁ . . . 406 ₅ toelongate from the untensioned condition in the direction X so as tocause the stretchable carrier 400 to exhibit a lengthen form.

The first, second and third form factors 502-506 represent only a smallfraction of the possible form factors of the stretchable carrier 400,any of which is easily discernable in view of the teachings herein.Moreover, certain form factors of the stretchable carrier 400 may resultfrom varying rates of change of the five stretchable parts 404 ₁ . . .404 ₅ (individually or collectively) and/or varying amounts offlexibility of the four mounting sites 402 ₁ . . . 402 ₄ (individuallyor collectively).

FIGS. 6A and 6B are simplified plan view diagrams illustrating anexample stretchable PV device 600. The stretchable PV device 600includes the stretchable carrier 400 (FIG. 4) and a PV cell 602. The PVcell 602 is similar to the PV cell 202 of FIG. 2A, except as describedherein.

The PV cell 602 may be disposed onto each of the stretchable-part-uppersurfaces 412 ₁ . . . 412 ₅ and each of the mounting-site-upper surfaces408 ₁ . . . 408 ₄ (collectively “carrier-upper surface”) such that theentire or substantially all of the back-contact layer 212 of the stack204 affixes to such surfaces and conforms to the undulating corrugationsof the five stretchable parts 404 ₁ . . . 404 ₅ and the forms of thefour mounting sites 402 ₁ . . . 402 ₄. Alternatively, the PV cell 602may be disposed onto the stretchable-part-upper surfaces 412 ₁ . . . 412₅ and each of the mounting-site-upper surfaces 408 ₁ . . . 408 ₄ suchthat the back-contact layer 212 of the stack 204 affixes to suchsurfaces only at certain locations and with or without conforming to anyof the undulating corrugations of the five stretchable parts 404 ₁ . . .404 ₅ or the forms of the four mounting sites 402 ₁ . . . 402 ₄. Thisway, the PV cell 602 and the five stretchable parts 404 ₁ . . . 404 ₅may elongate and/or compress at different rates, and/or within differentlimits of elongation and/or compression.

Although not shown, the stretchable PV device 600 may include one ormore buffer layers between the PV cell 602 and the carrier-upper surfaceto facilitate reduction of stresses and/or strains due to the PV cell602 and the stretchable carrier 400 having different rates of elongationand/or compression, and/or having different limits of elongation and/orcompression. And depending on desired orientation of the stack 204and/or application, a layer of the stack 204 other than the back-contactlayer 212 may be disposed onto or over the carrier-upper surface.Additionally, the stretchable PV device 600 may include a plurality ofPV cells, even though it is shown as including only one PV cell, namely,PV cell 602.

Like the stretchable PV device 200, the stretchable PV device 600 may beformed monolithically or hybridily. Under monolithic formation, thestretchable PV device 600 may be formed by (i) forming the stretchablecarrier 400, (ii) depositing the PV cell 602 or a plurality of PV cellsonto or over carrier-upper surface, and then (iii) carrying outappropriate post-deposition processes (e.g., using any of mechanical andlaser scribing to monolithically interconnect the plurality of PVcells).

Under hybrid formation, the stretchable PV device 600 may be formed byforming the carrier 400 and the PV cell 202 or plurality of PV cellsseparately from one another using separate processes. Thereafter, the PVcell 202 or plurality of PV cells may be affixed onto or over thecarrier-upper surface using a bonding agent or adhesive. After the PVcell 202 or the plurality of PV cells become affixed to the stretchablecarrier 400, appropriate post-affixing processes may be carried out. Forexample, the plurality of PV cells may be interconnected using any ofwire bonds, corrugated tabs, tapes and like-type electricalinterconnections.

Analogous to the stretchable carrier 400 of FIGS. 4A, 4B, and 5A-5C, thestretchable PV device 600 includes or is formed from one or morematerials that allow one or more of the five stretchable-part length 406₁ . . . 406 ₅ to change responsive to one or more of the applied forcesapplied to the stretchable PV device 600 or elements thereof.

FIGS. 7A and 7B are simplified plan view diagrams illustrating anexample stretchable PV device 700. The stretchable PV device 700includes the stretchable carrier 400 (FIG. 4) and four PV cells 702 ₁ .. . 702 ₄. Each of the PV cells 702 ₁ . . . 702 ₄ is similar to the PVcell 202 of FIG. 2A, except as described herein.

The PV cells 702 ₁ . . . 702 ₄ may be disposed onto themounting-site-upper surfaces 408 ₁ . . . 408 ₄, respectively, such thatthe entire or substantially all of the back-contact layers of PV cells702 ₁ . . . 702 ₄ affix to such surfaces and conform to the form of thefour mounting sites 402 ₁ . . . 402 ₄. Alternatively, the PV cells 702 ₁. . . 702 ₄ may be disposed onto the mounting-site-upper surfaces 408 ₁. . . 408 ₄, respectively, such that the back-contact layers of PV cells702 ₁ . . . 702 ₄ affix to such surfaces only at certain locations andwith or without conforming to the forms of the four mounting sites 402 ₁. . . 402 ₄. This way, the PV cells 702 ₁ . . . 702 ₄ and the fourmounting sites 402 ₁ . . . 402 ₄ may flex and/or bend at differentrates, and/or within different limits of permissible flexing or bending.

In addition, one or more of the electrical conductors of the PV cells702 ₁ . . . 702 ₄ may couple to the mounting-site contacts of the fourmounting sites 402 ₁ . . . 402. The electrical conductors of the PVcells 702 ₁ . . . 702 ₄ may also couple to the electrically-conductiveportions of the five stretchable parts 404 ₁ . . . 404 ₅ via theinterconnection paths or via in direct coupling.

As above, the stretchable PV device 700 may include one or more bufferlayers between the each of the PV cells 702 ₁ . . . 702 ₄ and the fourmounting sites 402 ₁ . . . 402 ₄ to facilitate reduction of stressesand/or strains due to the PV cells 702 ₁ . . . 702 ₄ and the fourmounting sites 402 ₁ . . . 402 ₄ having different rates of elongationand/or compression, and/or having different limits of elongation and/orcompression. And depending on desired orientation of each of the PVcells 702 ₁ . . . 702 ₄ and/or application, layers other than theback-contact layer of such cells may be disposed onto or over themounting-site-upper surfaces 408 ₁ . . . 408 ₄.

Like the stretchable PV device 600, the stretchable PV device 700 may beformed monolithically or hybridily. Under monolithic formation, thestretchable PV device 700 may be formed by (i) forming the stretchablecarrier 400, (ii) depositing the PV cells 702 ₁ . . . 702 ₄ onto or overthe four mounting sites 402 ₁ . . . 402 ₄, and then (iii) carrying outappropriate post-deposition processes (e.g., using any of mechanical andlaser scribing to monolithically interconnect the PV cells 702 ₁ . . .702 ₄).

Under hybrid formation, the stretchable PV device 700 may be formed byforming the stretchable carrier 400 separately from the PV cells 702 ₁ .. . 702 ₄ using separate processes. Thereafter, the PV cells 702 ₁ . . .702 ₄ may be affixed onto or over the four mounting sites 402 ₁ . . .402 ₄ using a bonding agent or adhesive. After the PV cells 702 ₁ . . .702 ₄ become affixed to the stretchable carrier 400, appropriatepost-affixing processes may be carried out. For example, the PV cells702 ₁ . . . 702 ₄ may be interconnected using any of wire bonds,corrugated tabs, tapes and like-type electrical interconnections.

Analogous to the carrier 400 of FIGS. 4A, 4B, and 5A-5C, the stretchablePV device 700 includes or is formed from one or more materials thatallow one or more of the five stretchable-part length 406 ₁ . . . 406 ₅to change responsive to one or more of the applied forces applied to thestretchable PV device 700 or elements thereof.

FIG. 8 is a simplified plan view diagram illustrating an examplestretchable carrier 800 for facilitating formation of any of astretchable PV device and stretchable PV module. The carrier 800 isarranged into an array of rows r, where r=1-7 and columns c, wherec=1-7, and includes stretchable parts 804 _(r,c) (where r+c is alwaysodd), mounting sites 802 _(r,c) (where each of r and c is always odd),and apertures 806 _(r,c) (where each of r and c is always even). Foravoidance of repetition and for the sake of simplicity, reference ismade to FIG. 4 when describing the stretchable carrier 800 or elementsthereof.

Each of the mounting sites 802 _(r,c) has a construction similar to anyone of the four mounting sites 402 ₁ . . . 402 ₄ (FIG. 4), and eachfunctions similar to any of such four mounting sites 402 ₁ . . . 402 ₄.The mounting sites 802 _(r,c), like the four mounting sites 402 ₁ . . .402 ₄, define respective surface areas. These surface areas haverespective geometries (“mounting-site geometries”); each of which may beany of a cross, square, circle, hexagon, triangle, trapezoid, tetragon,trapezium, deltoid, pentagon, rhomboid, polygon, etc.

Each of the stretchable parts 804 _(r,c) has a construction similar toany one of the five stretchable parts 404 ₁ . . . 404 ₅, and eachfunctions similar to any of the five stretchable parts 404 ₁ . . . 404₅. Like the five stretchable parts 404 ₁ . . . 404 ₅, the stretchableparts 804 _(r,c) define respective stretchable-part lengths 808 _(r,c).The stretchable parts 804 _(r,c) also define respective widths(“stretchable-part widths”) 810 _(r,c). These stretchable-part widths810 _(r,c) are generally transverse to the stretchable-part lengths 808_(r,c), and have respective geometries (“stretchable-part-widthgeometries”) to adapt or otherwise conform to the mounting-sitegeometries. Alternatively, the stretchable-part-width geometries and/orthe mounting-site geometries may take particular forms to accommodatevarious geometries of PV cells; various rates of flexion, elongation,compression, etc.; various desired form factors; and/or variousapplications.

Like the mounting sites 802 _(r,c), the nine apertures 806 _(r,c) definerespective geometries (“aperture geometries”); each of which may be anyof a cross, square, rectangle, circle, hexagon, triangle, trapezoid,tetragon, trapezium, deltoid, pentagon, rhomboid, octagon, etc. Theaperture geometries, the stretchable-part-width geometries and/or themounting-site geometries may take particular forms to accommodatevarious geometries of PV cells; various rates of flexion, elongation,compression, etc.; various desired form factors of the carrier 800;and/or various applications. Additionally and/or alternatively, theaperture geometries may take particular forms to allow electromagneticradiation to pass through the carrier 800 (or a PV device or moduleincorporating such stretchable carrier 800) as described in more detailbelow.

Although shown as including twenty-four stretchable parts, sixteenmounting sites, and nine apertures, the stretchable carrier 800 mayinclude more or fewer stretchable parts, mounting sites and/orapertures. And although the stretchable carrier 800 is shown as a squarearray, the stretchable carrier 800 may have a different geometry.

Referring now to FIG. 9, simplified plan view diagrams illustrating anexample stretchable carrier 900 for facilitating formation of any of astretchable PV device and stretchable PV module is shown. Like thestretchable carrier 800 of FIG. 8, the stretchable carrier 900 isarranged into an array of rows r, where r=1-7, and columns c, wherec=1-7; and includes twenty-four stretchable parts, namely, stretchableparts 904 _(r,c), which are positioned in the same rows and columns asthe stretchable parts (i.e., where r+c is always odd). The stretchablecarrier 900 differs from the stretchable carrier 800 of FIG. 8 in thatthe stretchable carrier 900 has (i) apertures, namely, apertures 906_(r,c) positioned in the same rows and columns as the mounting sites 802_(r,c) (i.e., where each of r and c is always odd); and (ii) mountingsites, namely, mounting sites 902 _(r,c) positioned in the same rows andcolumns as the apertures 806 _(r,c) (i.e., where each of r and c isalways odd).

The mounting sites 902 _(r,c) have constructions and function similar tothe mounting sites 802 _(r,c). The stretchable parts 904 _(r,c) haveconstructions and function similar to the stretchable parts 804 _(r,c).The apertures 906 _(r,c) have constructions similar to the apertures 806_(r,c).

Like the stretchable carrier 800, the aperture geometries of theapertures 906 _(r,c), the stretchable-part-width geometries of thestretchable parts 904 _(r,c) and/or the mounting-site geometries of themounting sites 902 _(r,c) may take particular forms to accommodatevarious geometries of PV cells; various rates of flexion, elongation,compression, etc.; various desired form factors of the stretchablecarrier 900 (or a PV device or module incorporating such carrier 900);and/or various applications. Additionally and/or alternatively, theaperture geometries of the apertures 906 _(r,c) may take particularforms to allow electromagnetic radiation to pass through the stretchablecarrier 900 (or a PV device or module incorporating such carrier 900) asdescribed in more detail below.

Although shown as including twenty-four stretchable parts, nine mountingsites, and sixteen apertures, the stretchable carrier 900 may includemore or fewer stretchable parts, mounting sites and/or apertures. Andalthough the stretchable carrier 900 is shown as a square array in whichthe stretchable parts are orthogonally positioned, the stretchablecarrier 900 may have a different geometry and the stretchable parts maybe positioned orthogonally or otherwise.

In some embodiments, a stretchable carrier may be constructed fromeither a single flexible film or foil, or from multiple foils, which maybe electrically insulating or conducting depending on the electricalinterconnection scheme, as illustrated below. Stretchable and mountingparts of the carrier may be manufactured and formed separately andsubsequently assembled and attached to each other to produce a singlecarrier. For example, metal (e.g., stainless steel, copper, aluminum,etc.) foils may be machined to form corrugated stretchable parts of thecarrier, whereas flat plastic (e.g., polyimide or the like) films may beused to produce mounting parts of the carrier. The stretchable parts maybe attached to the mounting parts using conventional adhesives. It is tobe understood that other sheet materials may be used to produce similarcarriers and also alternative carrier geometries may be utilized.

Alternatively, a stretchable carrier can be constructed entirely orpartially using wires, fibers, or grids and meshes of wires or fibers.For example, FIG. 25 depicts a stretchable carrier 2500 formed entirelyof a wire mesh 2501 according to some embodiments of the invention. Thewire mesh 2501 includes stretchable parts 2502 (e.g., corrugated parts)and mounting parts 2504. The wires of the wire mesh 2501 may be cut andformed using a single copper wire roll, for example. The corrugations inthe stretchable parts 2502 may be produced parallel to the plane of thecarrier 2500, rather than orthogonally to the plane of the carrier 2500.Separate wire sections in the wire mesh 2501 (i.e., stretchable parts2502 or mounting parts 2504) may be welded, soldered, or otherwisebonded together to produce a single carrier. Stretchable parts 2502 andmounting parts 2504 may be made of different wires or differentmaterials.

FIGS. 10A-10B are simplified plan view diagrams illustrating an examplestretchable PV device 1000. The stretchable PV device 1000 includes astretchable carrier 1002 and a plurality of PV cells 1004. For avoidanceof repetition and for ease of simplicity, the stretchable PV device 1000may be described with reference to the architectures of the stretchablecarrier 800 of FIG. 8 and the PV device 700 of FIGS. 7A and 7B. Thestretchable PV device 1000 may be implemented in other ways as well.

The stretchable carrier 800, as described above, defines two-dimensionalpositions for the stretchable parts 804 _(r,c) mounting sites 802 _(r,c)and apertures 806 _(r,c). These positions define a first pattern(“pattern A”). As shown in FIG. 8, this pattern A defines that (i) thepositions of the stretchable parts 804 _(r,c) are located at row andcolumn combinations where r+c is always odd, (ii) the positions of themounting sites 802 _(r,c) are located at row and column combinationswhere each of r and c is always odd, and (iii) the positions of theapertures 806 _(r,c) are located at row and column combinations whereeach of r and c is always even.

The stretchable carrier 1002, like the stretchable carrier 800, includesrespective pluralities of stretchable parts 1006, mounting sites 1008and apertures 1010. These pluralities of stretchable parts 1006,mounting sites 1008 and apertures 1010 are arranged according to thepattern A. And like the PV device 700, the plurality of PV cells 1002may be disposed over the mounting sites 1008.

The stretchable PV device 1000 includes or is formed from one or morematerials that allow one or more of the stretchable-part lengths of thestretchable parts 1006 to change responsive to one or more of theapplied forces applied to the stretchable PV device 1000 or elementsthereof. In addition, the stretchable PV device 1000 may be formedmonolithically or hybridily.

FIGS. 11A-11B are simplified plan view diagrams illustrating an examplestretchable PV device 1100. The stretchable PV device 1100 includes astretchable carrier 1102 and a plurality of PV cells 1104. For avoidanceof repetition and for ease of simplicity, the stretchable PV device 1100may be described with reference to the architectures of the stretchablecarrier 900 of FIG. 9 and the PV device 700 of FIGS. 7A and 7B. Thestretchable PV device 1100 may be implemented in other ways as well.

The stretchable carrier 900, as described above, defines respectivetwo-dimensional positions for the stretchable parts 904 _(r,c) mountingsites 902 _(r,c) and apertures 906 _(r,c). These positions define asecond pattern (“pattern B”). As shown in FIG. 9, the pattern B definesthat (i) the positions of the stretchable parts 904 _(r,c) are locatedat row and column combinations where r+c is always odd, (ii) thepositions of the mounting sites 902 _(r,c) are located at row and columncombinations where each of r and c is always even, and (iii) thepositions of the apertures 906 _(r,c) are located at row and columncombinations where each of r and c is always odd.

The stretchable carrier 1100, like the stretchable carrier 900, includespluralities of stretchable parts 1106, mounting sites 1108 and apertures1110. These pluralities of stretchable parts 1106, mounting sites 1108and apertures 1110 are arranged according to the pattern B. And like thePV device 700, the plurality of PV cells 1102 may be disposed over themounting sites 1108.

The stretchable PV device 1100 includes or is formed from one or morematerials that allow one or more of the stretchable-part lengths of thestretchable parts 1106 to change responsive to one or more of theapplied forces applied to the stretchable PV device 1100 or elementsthereof. Additionally, the stretchable PV device 1110 may be formedmonolithically or hybridly.

FIG. 26 depicts a stretchable carrier 2600 and a plurality of PV cells2602 according to some embodiments of the invention. The PV cells 2602may be mounted and attached to mounting sites 2604 of the stretchablecarrier 2600 using optional mounts 2606. The size of the PV cells 2602may be larger than the size of the mounting sites 2604. Conductingsections of the stretchable carrier 2600 may be used for electricalinterconnection between different ones of the PV cells 2602 either inparallel or in series, substantially as described above. Additionalelements may be used the present device to improve its performance. Forexample, additional rigid elements (e.g., square brackets) may be usedto strengthen the mounting sites 2604 of the device and protect the PVcells 2602 from potential damage due to uncompensated stress.

Referring now to FIGS. 12A-12B, simplified plan view diagramsillustrating an example stretchable PV module 1200 are shown. Thestretchable PV module 1200 includes a first stretchable device 1202overlaying a second stretchable device 1204. For avoidance of repetitionand for ease of simplicity, the stretchable PV module 1200 may bedescribed with reference to the architectures of the stretchable devices1000, 1100 of FIGS. 10A-10B and 11A-11B, respectively.

The first stretchable device 1202 has a construction similar to and alsofunctions similar to the stretchable device 1000 of FIGS. 10A-10B. Inaddition, the first stretchable device 1202 includes respectivepluralities of stretchable parts 1206, mounting sites 1208 and apertures1210 arranged according to the pattern A. The first stretchable device1202 also includes a plurality of PV cells 1212 disposed over themounting sites 1208.

The second stretchable device 1204 has a construction similar to andalso functions similar to the stretchable device 1100 of FIGS. 11A-11B.The second stretchable device 1204 includes respective pluralities ofstretchable parts 1214, mounting sites 1216 and apertures 1218 arrangedaccording to the pattern B. In addition, the second stretchable device1204 includes a plurality of PV cells 1220 disposed over the mountingsites 1216.

The first stretchable device 1202 may overlay the second stretchabledevice 1204 so as to align the first-stretchable-device apertures 1210over the second-stretchable-device PV cells 1220, and/or alignsecond-stretchable-device apertures 1218 over thefirst-stretchable-device PV cells 1212. By aligning this way,electromagnetic radiation may pass through the first-stretchable-deviceapertures 1210 to the second-stretchable-device PV cells 1220 Thiscombination allows for an effective active PV area or aperture greaterthan would be available by having only a single stretchable device.

The stretchable PV module 1200 may also include an encapsulation 1222.The encapsulation 1222 that encapsulates the first and secondstretchable devices 1202, 1204. The encapsulation 1222 includes firstand second coversheets 1224, 1226 separated by a layer of encapsulatingmaterial 1228; each of which may be constructed similar to and functionsimilar to like-type elements of the encapsulation 302 of FIG. 3.

As shown, the encapsulation 1222 entirely encapsulates the first andsecond stretchable devices 1202, 1204. The encapsulation 1222, however,may only encapsulate a portion of the first and second stretchabledevices 1202, 1204. In addition, the first stretchable device 1202 isshown as overlaying the second stretchable device 1204, the stretchablePV module 1200 may also be formed with the second stretchable device1204 overlaying the first stretchable device 1202.

FIG. 13 is a simplified plan view diagram illustrating an examplestretchable PV module 1300. The stretchable PV module 1300 includes afirst stretchable device 1302 overlaying a second stretchable device1304. For avoidance of repetition and for ease of simplicity, thestretchable PV module 1300 may be described with reference to thearchitectures of the stretchable devices 1000, 1100 of FIGS. 10A-10B and11A-11B, respectively.

The first stretchable device 1302 has a construction similar to, andalso functions similar to the stretchable device 1000 of FIGS. 10A-10B.In addition, the first stretchable device 1302 includes respectivepluralities of stretchable parts 1306, mounting sites 1308 and apertures1310 arranged according to the pattern A. The first stretchable device1302 also includes a plurality of PV cells 1312 disposed over themounting sites 1308. The first-stretchable-device PV cells 1312 and themounting sites 1308 may be at least partially transparent. This way,some fraction of electromagnetic radiation unabsorbed by thefirst-stretchable-device PV cells 1312 may pass thorough them and themounting sites 1308. The first-stretchable-device PV cells 1312 may be,for example, single-junction PV cells having a semiconductor absorberwith a characteristic bandgap E₁ in the range of 1.4 to 2.4 eV. By wayof example, the first-stretchable-device PV cells 1312 may be fabricatedfrom CGS (CuGaSe₂) so as to exhibit a 1.7 eV bandgap.

Like the first stretchable device 1302, the second stretchable device1304 has a construction similar to, and also functions similar to thestretchable device 1000 of FIGS. 10A-10B. In addition, the secondstretchable device 1304 includes respective pluralities of stretchableparts 1314, mounting sites 1316 and apertures 1318 arranged according tothe pattern A. The second stretchable device 1304 also includes aplurality of PV cells 1320 disposed over the mounting sites 1316. Thefirst-stretchable-device PV cells 1312 may be, for example,single-junction PV cells having a semiconductor absorber with acharacteristic bandgap E₂ in the range of 0.6 to 1.8 eV, so that E₂<E₁.The second-stretchable-device PV cells 1320 may be fabricated from CIS(CuInSe₂) so as to exhibit a 1.0 eV bandgap.

The first stretchable device 1302 may overlay the second stretchabledevice 1304 so as to align, at least in part, thefirst-stretchable-device PV cells 1312 over thesecond-stretchable-device PV cells 1320. By aligning this way,electromagnetic radiation may pass through the first-stretchable-devicePV cells 1312 to the second-stretchable-device PV cells 1320, which mayallow the stretchable PV module 1300 to function similar to knownmulti-junction PV devices and/or have a higher efficiency than having asingle junction stretchable-device.

In addition, the stretchable PV module 1300 may also include anencapsulation 1322. The encapsulation 1322 that encapsulates the firstand second stretchable devices 1302, 1304. The encapsulation 1322includes first and second coversheets 1324, 1326 separated by a layer ofencapsulating material 1328; each of which may be constructed similar toand function similar to like-type elements of the encapsulation 302 ofFIG. 3.

As shown, the encapsulation 1322 entirely encapsulates the first andsecond stretchable devices 1302, 1304. The encapsulation 1322, however,may only encapsulate a portion of the first and second stretchabledevices 1302, 1304.

As described, the first and second stretchable devices 1302, 1304 aresimilar to the stretchable device 1000 of FIG. 10. The first and secondstretchable devices 1302, 1304 may take other forms as well. Forexample, the first and second stretchable devices 1302, 1304 may besimilar to the stretchable device 1100 of FIG. 11.

Referring now to FIG. 14, a simplified plan view diagram illustrating anexample stretchable PV device 1400 is shown. The stretchable PV device1400 includes a stretchable carrier 1402, a plurality of pedestals 1404,and a plurality of PV cells 1406.

The stretchable carrier 1402 is similar to any of the aforementionedstretchable carriers, and includes pluralities of stretchable parts1408, mounting sites 1410, and optionally, apertures (not shown). Theplurality of pedestals 1404 may be disposed onto or over the mountingsites 1410, and the plurality of PV cells 1406 may be disposed onto orover the plurality of pedestals 1404.

Each of the plurality of pedestals 1404 may define dimensions that causethe PV cells 1406 to be positioned sufficiently above the stretchablecarrier 1402 to define an effective active PV area or aperture 1412greater than would be available by disposing the PV cells 1406 withinthe confines of the surfaces areas of the mounting sites 1410. Theplurality of pedestals 1404 and the plurality of PV cells 1406 may bedimensioned to allow, with respect to desired flexing, elongation and/orcompression, minimum spacing between adjacent PV cells 1406.

In addition to or in lieu of the plurality of pedestals 1404, thestretchable carrier 1402 may include additional substrates, heat sinks,submounts, or other like-type spacers. These spacers, like the pluralityof pedestals 1404, may provide an effective active PV area or aperture1412 greater than would be available by disposing the PV cells 1406within the confines of the surfaces areas of the mounting sites 1410. Inaddition, the plurality of pedestals 1404 and/or submounts may beelectrically conductive, and may provide electrical connectivity amongthe PV cells 1406, mounting-site contacts of the mounting sites 1410and/or positive and negative PV-cells terminals. The plurality ofpedestals 1404 and/or submounts increase performance, e.g., deviceefficiency, and improve manufacturing process, e.g., yield of hybridlyintegrated stretchable PV devices.

FIG. 15 is a simplified plan view diagram illustrating an examplestretchable PV device 1500. The stretchable PV device 1500 includes astretchable carrier 1502 and a plurality of PV cells 1504.

The stretchable carrier 1502 is similar to any of the aforementionedstretchable carriers, and includes pluralities of stretchable parts1506, mounting sites 1508, and optionally, apertures (not shown). Themounting sites 1508 may include respective mounting-site contacts madefrom electrically conducting materials, such as metal foils, laminatefilms with metal foils or composite films with embedded conductors. Asabove, these mounting-site contacts may electrically couple orinterconnect to the front and back contacts of PV cells 1504. Themounting sites 1508 may also include electrically insulating portionsfor providing electrical separation and insulation between differentcontacts and terminals.

The stretchable parts 1506 may also include electrically conductiveportions (“stretchable-part-conducting portions”) made from theelectrically conductive materials. The stretchable-part-conductingportions electrically couple or interconnect to the mounting-sitecontacts. Both positive and negative terminals of PV cells 1504 may belocated on the cells' backside and have direct electrical connection tothe mounting-site contacts.

The stretchable-part-conducting portions, mounting-site contacts and/orfront and back contacts of PV cells 1504 may be arranged to interconnectthe outputs of the PV cells 1504 in series or in parallel. In theformer, the stretchable-part-conducting portions, mounting-site contactsand/or the front and back contacts of PV cells 1504 may interconnect sothat positive terminals (e.g., back contacts) of the PV cells 1504 areconnected to negative terminals (e.g., front contacts) of the PV cells1504. In the latter, stretchable-part-conducting portions, mounting-sitecontacts and/or the front and back contacts of PV cells 1504 mayinterconnect so that the positive terminals of the PV cells 1504 areinterconnected, and the negative terminals of the PV cells 1504interconnected.

FIG. 16 is a simplified plan view diagram illustrating an examplestretchable PV device 1600. The stretchable PV device 1600 includes astretchable carrier 1602, a plurality of PV cells 1604 and connectors1612.

The stretchable carrier 1602 is similar to any of the aforementionedstretchable carriers, and includes pluralities of stretchable parts1606, mounting sites 1608, and optionally, apertures (not shown). Themounting sites 1608 may include mounting-site contacts that electricallycouple or interconnect to the back contacts of PV cells 1604. Inaddition, the stretchable parts 1606 may includestretchable-part-conducting portions that electrically couple orinterconnect to the mounting-site contacts.

The connectors 1612 may be made, at least in part, from electricallyconducting materials, and electrically couple or interconnect to thefront contacts of PV cells 1604. The connectors 1612 may be flexible andstretchable; and may be any of wire-bonded wires, corrugated tabs, tapesand the like.

The stretchable-part-conducting portions, mounting-site contacts, frontand back contacts of PV cells 1604 and/or connectors may be arranged tointerconnect outputs of the PV cells 1604 in series or in parallel. Inthe former, the stretchable-part-conducting portions, mounting-sitecontacts and/or the front and back contacts of PV cells 1604 mayinterconnect so that positive terminals (e.g., back contacts) of the PVcells 1604 are connected to negative terminals (e.g., front contacts) ofthe PV cells 1604. In the latter, stretchable-part-conducting portions,mounting-site contacts and/or the front and back contacts of PV cells1604 may interconnect so that the positive terminals of the PV cells1604 interconnect, and the negative terminals of the PV cells 1604interconnect.

FIGS. 17A and 17B are simplified plan view diagrams illustrating anexample stretchable PV device 1700. The stretchable PV device 1700includes a stretchable carrier 1702, a plurality of PV cells 1704, firstand second pluralities of mounting-site contacts 1706, 1707 and firstand second busbars 1708, 1710. For avoidance of repetition and for easeof simplicity, the stretchable PV device 1700 may be described withreference to the architectures of the stretchable devices 1000, 1600 ofFIGS. 10A-10B and FIG. 16, respectively.

The stretchable carrier 1702, like the stretchable carrier 1002,includes respective pluralities of stretchable parts 1712, mountingsites 1714 and apertures 1716. Like the PV device 1000, the plurality ofPV cells 1704 may be disposed onto or over the mounting sites 1714.

The stretchable PV device 1700 includes or is formed from one or morematerials that allow one or more of the stretchable-part lengths of thestretchable parts 1712 to change responsive to one or more of theapplied forces applied to the stretchable PV device 1700 or elementsthereof. In addition, the stretchable PV device 1700 may be formedmonolithically or hybridly.

First and second pluralities of mounting-site connectors 1706, 1707 haveconstructions similar to, and function similar to the connectors 1612shown in FIG. 16. The first plurality of mounting-site connectors 1706,in general, couple the positive terminals of the PV cells 1704(“PV-cells-positive terminals”) to the first busbar 1708; and the secondplurality of mounting-site connectors 1707, in general, couple thenegative terminals of the PV cells 1704 (“PV-cells-negative terminals”)to the second busbar 1710. The connectors 1612 may be flexible andstretchable; and may be any of wire-bonded wires, corrugated tabs, tapesand the like.

The first and second busbars 1708, 1710 are electrically conductive andinterconnect outputs of the PV cells 1704 in parallel. To facilitatethis, the first busbar 1708 includes a plurality of interconnection bars(“first-interconnecting bars”) 1718 electrically interconnected to atermination bar (“first-terminating bar”) 1720; and the second busbar1710 includes a plurality of interconnection bars(“second-interconnecting bars”) 1722 electrically interconnected to atermination bar (“second-terminating bar”) 1724. Each of thefirst-interconnecting bars 1718, first-terminating bar 1720,second-interconnecting bars 1722 and second-terminating bar 1724 iselectrically conductive, and may include or be made from electricallyconductive materials, such as any of metals and conductive polymers.

To facilitate interconnection, the first plurality of connectors 1706interconnect with the first-interconnecting bars 1718, whichinterconnects with the first-terminating bar 1720. In addition, thesecond plurality of connectors 1707 interconnect with thesecond-interconnecting bars 1722, and in turn, the first-interconnectingbars 1722 interconnect with the second-terminating bar 1724.

Under hybrid formation, the first and second busbars 1708, 1710 may bedeposited using, for example, by ink-jet or screen printing. Undermonolithic formation, the first and second busbars 1708, 1710 may bedeposited using deposition processes for thin-film materials. Undereither formation, the first and second busbars 1708, 1710 may bedeposited or otherwise disposed so that they are conformal with orotherwise formed over the stretchable parts 1712 and mounting sites 1714(and optionally, the apertures 1716). In addition, the materials of andthe form of the first and second busbars 1708, 1710 allow the first andsecond busbars 1708, 1710 to change in accordance with thestretchable-path lengths of the stretchable device 1700.

FIGS. 18A and 18B are simplified plan view diagrams illustrating anexample stretchable PV device 1800. The stretchable PV device 1800includes a stretchable carrier 1802, a plurality of PV cells 1804, firstand second pluralities of mounting-site connectors 1806, 1808 and aplurality busbars 1810. For avoidance of repetition and for ease ofsimplicity, the stretchable PV device 1800 may be described withreference to the architectures of the stretchable devices 1000, 1600 ofFIGS. 10A-10B and FIG. 16, respectively.

The stretchable carrier 1802, like the stretchable carrier 1002,includes respective pluralities of stretchable parts 1812, mountingsites 1814 and apertures 1816. Like the PV device 1000, the plurality ofPV cells 1804 may be disposed onto or over the mounting sites 1814.

The stretchable PV device 1800 includes or is formed from one or morematerials that allow one or more of the stretchable-part lengths of thestretchable parts 1812 to change responsive to one or more of theapplied forces applied to the stretchable PV device 1800 or elementsthereof. In addition, the stretchable PV device 1800 may be formedmonolithically or hybridly.

The busbars 1810 facilitate a series interconnection of the outputs ofthe PV cells 1804. To facilitate such series interconnection, each ofthe busbars 1810 is electrically conductive, and may include or be madefrom electrically conductive materials, such as any of metals andconductive polymers.

The first and second pluralities of mounting-site connectors 1806, 1807have constructions similar to, and function similar to the connectors1612 shown in FIG. 16. The first plurality of mounting-site connectors1806 couple the PV-cells-positive terminals of the PV cells 1804 tospecific ones of the busbars 1810; and the second plurality ofmounting-site connectors 1806 couple the PV-cells-negative terminals ofthe PV cells 1804 to specific ones of the busbars 1810. The connectors1612 may be flexible and stretchable; and may be any of wire-bondedwires, corrugated tabs, tapes and the like. The first and secondpluralities of mounting-site connectors 1806, 1807 are coupled tobusbars 1810 such that each of the PV cells 1804 is serially coupledwith an adjacent one of the PV cells 1804. The serial interconnection ofthe PV cells 1804 is shown by way of example as starting from the PVcell in the top left corner, proceeding across a row from left to row,proceeding down to the next row, proceeding across the next row fromright to left, proceeding down to the next row, and so on until the PVcell in the bottom right corner. It is to be understood that other typesof serial interconnections among the PV cells 1804 can be employed.

Under hybrid formation, the busbars 1810 may be deposited using, forexample, by ink-jet or screen printing. Under monolithic formation, thebusbars 1810 may be deposited using deposition processes for thin-filmmaterials. Under either formation, the busbars 1810 may be deposited orotherwise disposed so that they are conformal with or otherwise formedover the stretchable parts 1812 and mounting sites 1814 (and optionally,the apertures 1816). In addition, the materials of and the form of thebusbars 1810 allow the busbars 1810 to change in accordance with thestretchable-path lengths of the stretchable device 1800.

FIGS. 21 through 24 depict simplified plan view diagrams illustratingexample stretchable PV device 2100 having different types of stretchableparts according to some embodiments of the invention. FIG. 21 shows astretchable PV device 2100 having a stretchable carrier 2102 and aplurality of PV cells 2104. The stretchable carrier 2102 is similar toany of the aforementioned stretchable carriers, and includes pluralitiesof stretchable parts 2106, mounting sites 2108, and optionally,apertures (not shown). The stretchable PV device 2100 is similar to thatshown in FIGS. 15 and 16. However, in the present example, thestretchable parts 2106 may be implemented as elastic bands, rather thancorrugations. The elastic bands 2106 stretch in the plane of thestretchable carrier 2102 responsive to one or more applied forces.

FIG. 22 shows a stretchable PV device 2200 having the stretchablecarrier 2202 and a plurality of PV cells 2204. The stretchable carrier2202 is similar to any of the aforementioned stretchable carriers, andincludes pluralities of stretchable parts 2206, mounting sites 2208, andoptionally, apertures (not shown). However, in the present example, thestretchable parts 2206 may be implemented as hinges, rather thancorrugations. The hinges 2206 stretch in the plane of the stretchablecarrier 2202 responsive to one or more applied forces.

FIG. 23 shows a stretchable PV device 2300 having the stretchablecarrier 2302 and a plurality of PV cells 2304. The stretchable carrier2302 is similar to any of the aforementioned stretchable carriers, andincludes pluralities of stretchable parts 2306, mounting sites 2308, andoptionally, apertures (not shown). However, in the present example, thestretchable parts 2306 may be implemented as springs, rather thancorrugations. The springs 2306 stretch in the plane of the stretchablecarrier 2302 responsive to one or more applied forces.

FIG. 24 shows a stretchable PV device 2400 having the stretchablecarrier 2402 and a plurality of PV cells 2404. The stretchable carrier2402 is similar to any of the aforementioned stretchable carriers, andincludes pluralities of stretchable parts 2406, mounting sites 2408, andoptionally, apertures (not shown). However, in the present example, thestretchable parts 2406 may be implemented as rails, rather thancorrugations. The rails 2406 stretch in the plane of the stretchablecarrier 2402 responsive to one or more applied forces.

FIG. 19 is a flow diagram illustrating an example process 1900 forforming a stretchable photovoltaic device under monolithic formation.For avoidance of repetition and for ease of simplicity, the followingdescribes the process 1900 with reference to the architecture of thestretchable device 400 of FIG. 4, first; and then, describes the process1900 with reference to the architectures of the stretchable devices1000, 1500, 1700 and 1800 of FIGS. 10A-10B, FIG. 15, FIG. 17 and FIG.18, respectively, second. The process 1900 may be carried out usingother architectures as well.

The flow 1900 starts at termination block 1902, and sometime thereafter,transitions to process block 1904. At the process block 1904, theprocess 1900 forms the stretchable carrier 102. To do this, the process1900 may deposit one or more metals and/or plastics over a given form soas to form a foil in the form the corrugations 108 ₁ . . . 108 _(n). Theprocess 1900 may deposit the metals using, for example, physical vapordeposition (“PVD”). The metals and plastics may include, for example,any of stainless steel, aluminum and copper, polyimide, polyethylene,ethylene vinyl acetate (EVA), and the like. The foil, and in turn, thestretchable carrier 102 may have an ultimate thickness between about 10to 200 microns or between about 25 to 100 microns, although otherthicknesses are possible.

After process block 1904, the process 1900 may transition to processblock 1906. At the process block 1906, the process may form the PV cell202 over the stretchable carrier 102. To form the PV cell 202, theprocess 1900 may deposit the thin-film materials noted above to form thePV stack 204. This may include the process 1900 using any of PVD, CVD,ALD and the like to deposit the PV-stack layers onto or over the foil ofthe stretchable carrier 102.

By way of example, the process 1900 may deposit the PV stack 204 inwhich the n-type and p-type semiconductor layers 206, 208 together are asingle junction formed from GIGS (“CIGS junction”). To do this, theprocess 1900 may first deposit (e.g., by sputtering) a layer ofmolybdenum having a thickness between about 0.5-1 μm onto (or over) themetal foil of the stretchable carrier 102 so as to form the back-contactlayer 212.

After depositing the back-contact layer 212, the process 1900 may formthe CIGS junction. This may include the process 1900 depositing (e.g.,by sputtering) a layer of CIGS, e.g. a layer of CuIn_(0.3)Ga_(0.7)Se₂,having an ultimate thickness of about 1-3 μm onto (or over) theback-contact layer 212. After depositing the CIGS junction, the process1900 may deposit (e.g., by wet chemical bath deposition) a layer ofcadmium sulfide (“CdS”) having an ultimate thickness of about 30-100 nm.This CdS layer is a window layer to the CIGS junction, and as such,allows electromagnetic radiation to pass to the underlying CIGSjunction.

After depositing the window layer, the process 1900 may deposit anoptional buffer layer of undoped zinc oxide (“ZnO”). This buffer layermay protect the pn junction region from subsequent harsh processingsteps, such as sputtering. Also, this layer may function as a transportbarrier layer against minority carriers and thus improve deviceefficiency. In addition, this layer may reduce the shunt resistance ofthe device and also improve the device efficiency.

After depositing the buffer layer, the process 1900 may deposit (e.g.,by sputtering) a layer of aluminum doped ZnO (“Al:ZnO”) or,alternatively, a layer of indium oxide doped tin (In₂O₃:Sn or “ITO”) asa transparent front-contact layer 210. After or during formation of thePV stack 204, the process 1900 may form the first and second conductors209, 211 by appropriately depositing thin film material and/or formingvias in the PV stack 204 so as to permit interconnection with the frontand back contact layers 210, 212, respectively.

Although the foregoing describes the process 1900 forming the PV stack204 with only a single junction, the process 1900 may also carry outforming the PV stack 204 with more than one junction. To do this, forexample, the process 1900 may deposit more and/or different layers thandescribed above.

While the foregoing also describes the process 1900 as forming the PVstack 204 as a single PV cell, the process 1900 may also form the PVstack 204 with a plurality of PV cells. To facilitate this, the process1900 at the process block 1906 may be modified to include one or moreprocesses to form the plurality of PV cells. For example, the process1900 may include a laser, mechanical or other type of scribing of theback-contact layer 212 to separate the back-contact layer 212 into aplurality of discrete back contacts. In addition, after formation ofeach of the GIGS, window, buffer, transparent front-contact layer 210,etc., the process 1900 may laser, mechanically or otherwise scribe eachof such layers into discrete portions that match the shape andorientation of the discrete back contacts. These discrete portions formthe plurality of PV cells.

After process block 1906, the process 1900 may transition to processblock 1908. At the process block 1908, the process 1900 may interconnectthe PV cell 202 to the output terminals of the PV device 200. To dothis, the process 1900 may interconnect the first and second conductors209, 211 to the first and second output terminals 205, 207,respectively. To facilitate such interconnection, the process 1900 maydeposit metals to form wires between the first and second conductors209, 211 to the first and second output terminals 205, 207,respectively. Alternatively, the process 1900 may wirebond wires orprint conductive traces between (i) the first conductor 209 and thefirst output terminal 205, and/or (ii) the second conductors 211 and thesecond output terminal 207. Any combination of the foregoing is possibleas well.

While the foregoing also describes the process 1900 as interconnecting asingle PV cell, namely, PV cell 204, the process 1900 may alsointerconnect a plurality of PV cells in series and/or in parallel. Tofacilitate this, the process 1900 at the process block 1908 may bemodified to include one or more processes to interconnect the pluralityof PV cells. For example, the process 1900 may interconnect each of theplurality of PV cells by wirebonding wires or printing conductivetraces, as appropriate, between the PV-cells-positive terminals,PV-cells-negative terminals, the first output terminal 205, and/or thesecond output terminal 207.

After process block 1908, the process 1900 may transition to terminationblock 1910. At the termination block 1910, the process 1900 ends.Alternatively, the process 1900 may be repeated periodically, incontinuous fashion, or upon being triggered as a result of a condition.

Referring back to process block 1904 and with respect to the PV device1000, the process 1900 may form the stretchable carrier 1002. To dothis, the process 1900 may form the stretchable parts 1006 and mountingsites 1008 similar to forming the stretchable carrier 102 as describedabove. For example, the process 1900 may deposit one or more metalsand/or plastics over a given form so as to form a foil in the form thestretchable parts 1006 and mounting sites 1008. The process 1900 maydeposit the metals and/or plastics using, for example, PVD or CVD. Themetals and plastics may include, for example, any of as stainless steel,aluminum and copper, polyimide, polyethylene, ethylene vinyl acetate(EVA), and the like. The foil, and in turn, the stretchable parts 1006and mounting sites 1008 may have an ultimate thickness between about 10to 200 microns or between about 25 to 100 microns.

In addition, the process 1900 may machine or otherwise remove theapertures 1010 from the foil. After process block 1904, the process 1900may transition to process block 1906.

At the process block 1906, the process may form the plurality of PVcells 1004 over the stretchable parts 1006 and/or mounting sites 1008.To form the plurality of PV cells 1004, the process 1900 may deposit thethin-film materials noted above to form respective PV stacks. To dothis, the process 1900 may use any of PVD, CVD, ALD and the like todeposit the PV-stack layers of each of the respective PV stacks onto orover the foil of the stretchable parts 1006 and mounting sites 1008. Theprocess 1900 may do this in accordance with the example described abovewith respect to the PV stack 204.

After process block 1906, the process 1900 may transition to processblock 1908. At the process block 1908, the process 1900 may interconnectthe plurality of PV cells 1004 to the output terminals of the PV device1000. To facilitate this, the process 1900 may appropriatelyinterconnect the first and second conductors of each of the plurality ofPV cells to form series or parallel interconnection. Then, the process1900 may interconnect the interconnected PV cells to the outputterminals 205, 207. To facilitate such interconnection, the process 1900may deposit metals to form wires or alternatively wirebond wires orprint conductive traces as described above with respect to the PVdevices 1700, 1800 of FIGS. 17 and 18, respectively. Any combination ofthe foregoing is possible as well.

After process block 1908, the process 1900 may transition to terminationblock 1910. At the termination block 1910, the process 1900 ends.Alternatively, the process 1900 may be repeated periodically, incontinuous fashion, or upon being triggered as a result of a condition.

FIG. 20 is a flow diagram illustrating an example process 2000 forforming a stretchable photovoltaic device under hybrid formation. Foravoidance of repetition and for ease of simplicity, the followingdescribes the process 2000 with reference to the architectures of thestretchable devices 200, 600, 700, 1000, 1500, 1700 and 1800 of FIGS. 2,6, 7, 10A-10B, FIG. 15, FIG. 17 and FIG. 18, respectively. The process2000 may be carried out using other architectures as well.

The flow 2000 starts at termination block 2002, and sometime thereafter,transitions to process block 2004. At the process block 2004, theprocess 2000 may form the stretchable carrier 1002. To do this, theprocess 2000 may form the stretchable parts 1006 and mounting sites 1008similar to forming the stretchable carrier 102 as described above. Forexample, the process 2000 may deposit one or more metals and/or plasticsover a given form so as to form a foil in the form the stretchable parts1006 and mounting sites 1008.

The process 2000 may deposit the metals and/or plastics. The metals andplastics may include, for example, any of as stainless steel, aluminumand copper, polyimide, polyethylene, ethylene vinyl acetate (EVA), andthe like. The foil, and in turn, the stretchable parts 1006 and mountingsites 1008 may have an ultimate thickness between about 10 to 200microns or between about 25 to 100 microns. In addition, the process2000 may machine or otherwise remove the apertures 1010 from the foil.

Alternatively, the process 2000 may form the stretchable parts 1006separately from the mounting sites 1008, and then join the stretchableparts 1006 with the mounting sites 1008. For example, the process 2000may form the stretchable parts 1006 from an from metal or plastic foils(or from an elastic material not having corrugations), and form themounting sites 1008 from metal or plastic foils. Thereafter, the process2000 may join or otherwise attach the foils together. In one particularembodiment, each of the mounting sites 1008 may have a surface area in arange of about 1 to 300 mm² or in a range of about 10 to 100 mm². And anoverall area of the stretchable carrier 1002 may be in a range of about0.1 to 2 m².

After process block 2004, the process 2000 may transition to processblock 2006. At the process block 2006, the process 2000 may form theplurality of PV cells 1004. To form the plurality of PV cells 1004, theprocess 2006 may deposit or process semiconductor materials noted aboveto form respective PV stacks over respective substrates. To do this, theprocess 2006 may use any of PVD, CVD, ALD and the like to deposit thePV-stack layers of each of the respective PV stacks onto or over theplurality of substrates, which may be flexible or rigid. The process2006 may do this in accordance with the example described above withrespect to the PV stack 204. In addition, the PV cells may becrystalline or polycrystalline Si cells, GIGS cells on glass substrates,high-efficiency III-V multi-junction cells (e.g. GaAs-based cells), etc.After the process block 2006, the process 2000 may transition to processblock 2008.

At the process block 2008, the process 2000 may combine the plurality ofPV cells 1004 with the stretchable carrier 1002. The process 2000 may doso by mounting, affixing or otherwise attaching the each of theplurality of PV cells 1004 onto (or over) the mounting sites 1008. Theprocess 2000 may use one or more bonding agents or adhesives to attachthe plurality of PV cells 1004 to the mounting sites 1008. As analternative, the process 2000 may attach pedestals or spacers to themounting sites 1008, and then attach, respectively, the plurality of PVcells to the pedestals or spacers. After the process block 2008, theprocess 2000 may transition to process block 2010.

At the process block 2010, the process 2000 may interconnect theplurality of PV cells 1004 to the output terminals of the PV device1000. To facilitate this, the process 200 may appropriately interconnectthe first and second conductors of each of the plurality of PV cells toform a series or parallel interconnection. Then, the process 2000 mayinterconnect the interconnected PV cells to the output terminals 205,207. To facilitate such interconnection, the process 2000 may depositmetals to form wires or alternatively wirebond wires or print conductivetraces as described above with respect to the PV devices 1700, 1800 ofFIGS. 17 and 18, respectively. Any combination of the foregoing ispossible as well.

After process block 2010, the process 2000 may transition to terminationblock 2012. At the termination block 2012, the process 2000 ends.Alternatively, the process 2000 may be repeated periodically, incontinuous fashion, or upon being triggered as a result of a condition.

CONCLUSION

Variations of the method, apparatus and system described above arepossible without departing from the scope of the invention. In view ofthe wide variety of embodiments that can be applied, it should beunderstood that the illustrated embodiments. In addition, those skilledin the art will appreciate that the present invention has applicabilityin many arenas. For example, one or more embodiments of the presentinvention may be used in or form, at least a part of, a skin ofautomotive body or body panel, and be used to provide electrical energyto a battery or a motor. In addition, similar embodiments of the presentinvention may be used with other types of vehicles, such as planes,trains, trucks, ships, weather balloons, airships, satellites, spaceships, orbital stations and others.

Furthermore, embodiments of the present invention may be used in manyother applications, for example, providing extra electrical power incars and other vehicles, recharging batteries in personal devices andappliances, providing independent power in monitoring and sensoringequipment, etc. Some embodiments of the present invention may be used inwearable electronic devices that may be flexible and stretchable. Inaddition, embodiments of the present invention may also facilitate largevolume production and widespread usage of photovoltaic devices.

The foregoing description of preferred embodiments of the presentinvention provides illustration and description, but is not intended tobe exhaustive or to limit the invention to the precise form disclosed.Modifications and variations are possible in light of the aboveteachings or may be acquired from practice of the invention. Forexample, any of the stretchable substrate 102 (FIG. 1) and thestretchable parts of the stretchable carriers, stretchable devicesand/or stretchable modules might not be or include corrugations.Instead, any of the stretchable substrate 102 and stretchable parts maybe or include any of elastic or elastic-like devices, deformable andpliant springs, mechanical rails and others devices that arestretchable.

No element, act, or instruction used in the description of the presentapplication should be construed as critical or essential to theinvention unless explicitly described as such. Also, as used herein, thearticle “a” is intended to include one or more items. Where only oneitem is intended, the term “one” or similar language is used. Further,the terms “any of” followed by a listing of a plurality of items and/ora plurality of categories of items, as used herein, are intended toinclude “any of,” “any combination of,” “any multiple of,” and/or “anycombination of multiples of” the items and/or the categories of items,individually or in conjunction with other items and/or other categoriesof items.

Exemplary embodiments have been illustrated and described. Further, theclaims should not be read as limited to the described order or elementsunless stated to that effect. In addition, use of the term “means” inany claim is intended to invoke 35 U.S.C. § 112, ¶ 6, and any claimwithout the word “means” is not so intended.

What is claimed is:
 1. A carrier comprising: a stretchable part having astretchable-part length, wherein the stretchable-part length is operableto change a length dimension of the carrier in response to a force beingapplied to the carrier, wherein the stretchable part comprises aplurality of corrugations, and wherein the change in thestretchable-part length is produced by a change in an amplitude andwidth of at least some of the plurality of corrugations; and a mountingsite having a flat foundation surface located between at least some ofthe plurality of corrugations on which to affix at least onephotovoltaic cell; wherein the stretchable part comprises first andsecond stretchable parts having respective first and second stretchablepart lengths, wherein the first stretchable part is orientedorthogonally to the second stretchable part, and wherein the firststretchable part length is operable to change independently from thesecond stretchable part length.
 2. A stretchable photovoltaic devicecomprising: a stretchable part having a stretchable-part length, whereinthe stretchable-part length is operable to change a length dimension ofthe stretchable photovoltaic device in response to a force being appliedto the stretchable photovoltaic device, wherein the stretchable partcomprises a plurality of corrugations, and wherein the change in thestretchable-part length is produced by a change in an amplitude andwidth of at least some of the plurality of corrugations; at least onephotovoltaic cell; and a mounting site having a flat foundation surfacelocated between at least some of the plurality of corrugations on whichthe at least one photovoltaic cell is disposed; wherein the stretchablepart comprises first and second stretchable parts having respectivefirst and second stretchable-part lengths, wherein the first stretchablepart is oriented orthogonally to the second stretchable part, andwherein the first stretchable-part length is operable to changeindependently from the second stretchable-part length.